A method of forming a pattern film at a target position by discharging an ion beam to a predetermined position on the sample in an atmosphere where compound vapor exists, in presently receiving attention as a repairing method for semiconductors and masks. As a method to supply the compound vapor to the target position on the sample, the Knudsen cell method described in "New Course 2 of Experimental Chemistry" published by Maruzen, Nov. 20, 1978, pages 371 to 379, is being utilized. As shown in FIG. 4, a Knudsen cell 52, in which compound 51 is stored inside, is heated by heater 53 provided on the outer circumferential portion, and the compound evaporated by the heating is ejected through an orifice 54. As shown, a thermo couple 55 is provided on the Knudsen cell 52 so that it is possible to control the heating temperature with a temperature controller, and to control the ejection amount of the compound vapor.
Also, as a similar method to form a pattern film utilizing the reaction between a charged particle beam and a chemical compound, the following method has been proposed in the draft manuscript of a lecture on "The Injection of Ions and the Processing of Submicrons" of the 15th symposium held in the Physico Chemical Research Institute. In this method, which is described in FIG. 5, the compound vapor 56 is supplied to a sub-sample chamber 58 provided within a sample chamber 57, and then an electron beam 60 discharged from an electron gun 59 is applied to the sample 56 through a small bore 61 provided in sub-sample chamber 58.
In the method described in FIG. 4, the compound vapor ejected from the orifice 54 fans out and spreads in a broad area without any directional characteristics. In general, the region to which the charged particle beam is applied to form the pattern film is smaller than 1.times.1 mm. Therefore, the compound vapor directed to anywhere beyond the target position is wasted, and causes various disadvantages. For example, when the compound adheres to undesired areas, the quantity of compound vapor supplied to the intended area at which the pattern film is to be formed may change as time passes, or when a charged particle beam such as an ion beam is utilized, it may cause deterioration of the series (for example, the life span of the ion source is reduced), as the compound adheres to the charged particle beam series.
Also, in the method described in FIG. 5, as it utilizes a sub-sample chamber inside the sample chamber, the driving mechanism for positioning the sample is complicated, and it is difficult to detect the defects of the mask. Furthermore, the following three mechanisms are required for a mask-repairing device that utilizes ion beam: a defect repairing mechanism which forms a thin film by the reaction between the compound vapor and the ion beam; a defect repairing mechanism which removes an unnecessary thin film by ion beam sputtering; and a sample surface detecting mechanism which utilizes secondary charged particles. Therefore, at the time of repairing an insufficiently formed film, the compound vapor is guided into the sub-sample chamber, but at the time of removing an unwanted portion of a formed film, the partial pressure of the vapor inside the sub-sample chamber must be sufficiently low to enable effective sputtering. Consequently, the mask-repairing device utilizing the sub-sample chamber has the disadvantage that it takes to much time in controlling the ON-OFF condition of the compound vapor.
The present invention has been devised to solve the above problems, and one object of the invention is to provide a mask-repairing device that easily controls the ON-OFF conditions of the ejection of the compound vapor by applying the vapor directionally without polluting unnecessary areas.
Also, another object of the present invention is to provide a mask-repairing device that can form a thin film not only on a flat portion of the sample but also on a recessed portion of the sample which is adjacent to the pattern, with the same conditions.
Furthermore, another object of the present invention is to provide a mask-repairing device that reduces the ejection amount of the compound vapor to prevent the inside of the sample chamber from being polluted and to prolong the life span of the ion source.
Further still, an object of the present invention is to provide a mask-repairing device where, by providing an interlock circuit, the contact between the nozzle tip and the sample palette guard is prevented, and the reliability of the device is improved.